A 44-year-old man with a history of chronic bronchitis is admitted with severe shoness of breath and left-sided chest pain. CXR is shown in. EKG shows left ventricular strain.What is the most likely diagnosis to explain the symptoms?
**Core Concept**
Pulmonary embolism (PE) is a life-threatening condition characterized by the blockage of one or more pulmonary arteries by a blood clot, leading to impaired gas exchange and potentially fatal complications. The clinical presentation of PE can be acute and severe, often manifesting as sudden onset dyspnea, chest pain, and tachycardia.
**Why the Correct Answer is Right**
The patient's history of chronic bronchitis may be a risk factor for deep vein thrombosis (DVT), which can lead to PE. The EKG finding of left ventricular strain suggests that the patient's cardiac output is compromised, likely due to the PE. This is supported by the CXR findings, which may show the "Westermark sign" (a wedge-shaped area of oligemia distal to the PE) or the "Hampton hump" (a rounded, well-circumscribed area of consolidation at the lung periphery). The patient's symptoms of severe shortness of breath and left-sided chest pain are consistent with a large PE causing a significant obstruction of blood flow to the lung.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because while pneumonia can cause acute respiratory distress, it would not typically present with left ventricular strain on EKG or the characteristic CXR findings of PE.
**Option B:** This option is incorrect because chronic bronchitis is a chronic condition, and an acute exacerbation would not typically be associated with left ventricular strain or the specific CXR findings of PE.
**Option C:** This option is incorrect because while acute myocardial infarction (AMI) can cause chest pain and shortness of breath, it would typically present with ST-segment elevation on EKG and not left ventricular strain.
**Clinical Pearl / High-Yield Fact**
In patients with suspected PE, a normal D-dimer test can help to rule out PE, but a negative D-dimer does not guarantee the absence of PE, especially in patients with a history of cancer, recent surgery, or immobilization.
**Correct Answer: C. Pulmonary Embolism.**